Integrated electronic module for 3d sensing applications, and 3d scanning device including the integrated electronic module

ABSTRACT

A method of manufacturing an electronic module includes providing a base substrate having a first surface, providing a first supporting element having a first portion with an inclined top surface, and affixing the first supporting element to the first surface such that the inclined top surface is inclined with respect to the base substrate. A first reflector is coupled to the inclined top surface such that a rear surface of the first reflector is in physical contact with the inclined top surface of the first portion of the first supporting element, and a spacer structure is configured to form an interface for mounting lateral walls to the base substrate. A cap is positioned over and supported by the lateral walls to thereby define a chamber. The emitter, as well as a detector, are coupled to the first surface of the base substrate.

PRIORITY CLAIM

This application is a continuation of U.S. application patent Ser. No.16/826,983, filed Mar. 23, 2020, which claims the priority benefit ofItalian Application for Patent No. 102019000004197, filed on Mar. 22,2019, the contents of which are hereby incorporated by reference intheir entireties to the maximum extent allowable by law.

TECHNICAL FIELD

This disclosure relates to an electronic module, to be used for threedimensional (3D) sensing applications, and to a 3D scanning deviceincluding the integrated electronic module.

BACKGROUND

With the introduction of the depth-sensing technology, the usage of 3Dsensing is now widely used on smartphones and portable devices ingeneral. In particular, the technology is expected to innovate thesecurity methods through face recognition.

One of the known methods to implement 3D sensing is based on atime-of-flight (ToF) approach. A typical ToF architecture includes aninfrared (IR) source configured to generate an IR light pulse towards anobject (emitted beam). A beam reflected by the object is received by adetector. Depth is calculated by measuring the time (direct ToF) or thephase shift (indirect ToF) between the emitted and the reflected beam.This approach has several advantages, among which a longer range withhigher accuracy and less required power, low processing requirements,accurate minimum object distance (MOD) thanks to higher angularresolution, and high immunity to blare effect (in case of objects inmotion). However, it is sensitive to reflections and scatteringphenomena.

Another known method to implement 3D sensing is based on structuredlight. In this case, a known pattern is projected onto an object; thepattern thus projected is distorted by the object, and an analysis ofthe distortion of the light pattern can be used to calculate a depthvalue and achieve a geometric reconstruction of the object's shape. Thistechnique has the advantages of being less sensitive to reflection andscattering and to allow the implementation of high volume solutions withan ongoing cost-optimization path. However, it requires heavyprocessing, complex component assembly and the resolution is limited bythe component's resolution.

It is known to implement the systems discussed above with a splitprojection/detection scheme, such as a solution where the projector andthe detector are each contained within their own package and physicallyseparated from each other, even though they might be mounted on a sameprinted-circuit board. In particular, the projector typically includes aLASER source and a micro-mirror manufactured in microelectromechanicalsystem (MEMS) technology; the LASER source is oriented so that a beam isdirected towards the micro-mirror, and the micro-mirror is controlled inoscillation to direct the beam towards a target. The main limitation ofthis approach is the system complexity and the need to cooperate withpartners that can design and manufacture opto-mechanical solutions.Moreover, by having the projector and the detector mounted as separatemodules, the integration is reduced and the size of the final moduleincreased. Smaller dimensions can be achieved to the detriment of thesystem performance.

There is therefore a need in the art for a technical solution theovercomes the above issues and drawbacks of the known art without havingan impact on the performance.

SUMMARY

Disclosed herein is a method of manufacturing an electronic module,including: integrating electronic circuitry for controlling an emitterand electronic circuitry for processing a detector output signal into abase substrate having a first surface; providing a first supportingelement formed from a solid body of metal acting as a heat-sink andhaving a first portion with an inclined top surface, and affixing thefirst supporting element to the first surface of the base substrate suchthat the inclined top surface of the first supporting element isinclined with respect to the base substrate; coupling a first reflectorto the inclined top surface of the first portion of the first supportingelement such that a rear surface of the first reflector is in physicalcontact with the inclined top surface of the first portion of the firstsupporting element; configuring a spacer structure to form an interfacefor mounting lateral walls to the base substrate, and positioning a capover and supported by the lateral walls to thereby define a chamber;coupling the emitter to the first surface of the base substrate in afashion such that the emitter is connected to the electronic circuitryfor controlling the emitter; and affixing a detector to the firstsurface of the base substrate in a fashion such that the detector isconnected to the electronic circuitry for controlling the detector.

The first supporting element may be affixed to the first surface of thebase substrate by gluing the first supporting element to the firstsurface of the base substrate.

The first supporting element may be formed from the solid body of metalto have a second portion extending parallel to the base substrate whenthe first supporting element is affixed to the first surface of the basesubstrate.

The emitter may be coupled to the first surface of the base substrate bycoupling the emitter to the second portion of the first supportingelement.

The first supporting element may be formed from the solid body of metalsuch that the first and second portions of the first supporting elementare integrally formed.

The first supporting element may be formed from the solid body of metalsuch that the first and second portions of the first supporting elementare separate from one another and spaced apart from one another.

The method may further include: thermally coupling a rigid-flex circuitto the inclined top surface of the first supporting element by thermallycoupling a first rigid portion of the rigid-flex circuit to the firstportion of the first supporting element, thermally coupling a secondrigid portion of the rigid-flex circuit to the second portion of thefirst supporting element, and connecting the first and second rigidportions of the rigid-flex circuit using a flexible portion, theflexible portion extending at an intersection between the first rigidportion and the second rigid portion such that it follows a change inslope between the first and second portions of the first supportingelement; wherein the emitter is coupled to the second portion of thefirst supporting element by affixing the emitter to the second rigidportion of the rigid-flex circuit; and wherein the first reflector iscoupled to the first portion of the first supporting element by affixingthe first reflector to the first rigid portion of the rigid-flexcircuit.

The electronic circuitry for controlling the emitter may be integratedinto the second rigid portion of the rigid-flex circuit.

The method may also include connecting a first end of a further flexibleportion of the rigid-flex circuit to the second rigid portion andconnecting a second end of the further flexible portion of therigid-flex circuit to one or more pads for supplying driving signals andpower supply to the first reflector.

The spacer structure may also be configured to completely surround aregion of the base substrate in which the first supporting element,first reflector, emitter, and detector are located.

The method may also include providing the spacer structure to be madefrom plastic material, metallic material, and/or semiconductor material;and further comprising providing the base substrate to be made from anorganic material, plastic material, and/or semiconductor material.

The method may also include providing the cap to include a secondsupporting element extending from an interior surface of the cap towardthe emitter; and further comprising affixing a second reflector to thesecond supporting element.

Also disclosed herein is a method of manufacturing an electronic module,including: integrating electronic circuitry for controlling an emitterand electronic circuitry for processing a detector output signal into abase substrate having a first surface; coupling a first reflector to afirst surface of the base substrate; configuring a spacer structure toform an interface for mounting lateral walls to the base substrate, andpositioning a cap over and supported by the lateral walls to therebydefine a chamber; coupling the emitter to the first surface of the basesubstrate in a fashion such that the emitter is connected to theelectronic circuitry for controlling the emitter; affixing a detector tothe first surface of the base substrate in a fashion such that thedetector is connected to the electronic circuitry for controlling thedetector; providing a lens module including first and second lenses; andpositioning the lens module within the chamber such that it is supportedby the spacer structure and extends therefrom parallel to the substratesuch that the first lens is operatively coupled to the emitter and thesecond lens is operatively coupled to the detector.

The spacer structure may also be configured to surround a region of thebase substrate in which the first reflector, emitter, and detector arelocated.

The method may also include providing the spacer structure to be madefrom plastic material, metallic material, and/or semiconductor material,and providing the base substrate to be made from an organic material,plastic material, and/or semiconductor material.

The method may include providing the cap to include a second supportingelement extending from an interior surface of the cap toward theemitter, and affixing a second reflector to the second supportingelement.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding, preferred embodiments thereof are nowdescribed purely by way of non-limiting example with reference to theattached drawings, wherein:

FIGS. 1 to 4 show respective cross-sectional views of electronic modulesaccording to respective embodiments;

FIG. 5A-10 show a cross-sectional and top-plan views of an electronicmodule during manufacturing steps;

FIG. 11 shows the electronic module manufactured according to the stepsof FIGS. 5A-10; and

FIG. 12 schematically shows a system including the electronic moduleusing any of the embodiments of FIGS. 1-4 and 11.

DETAILED DESCRIPTION

FIG. 1 shows, in a Cartesian (triaxial) reference system of axis X, Y,Z, an electronic module 1 to be used for 3D-sensing applications,according to an embodiment.

The electronic module 1 includes a package 2 formed by a base substrate2 a and a cap 2 b. The base substrate 2 a has a first surface 2 a′opposite to a second surface 2 a″. In the reference system of FIG. 1,the first and the second surfaces 2 a′, 2 a″ are parallel to one anotherand to the XY plane. Analogously, the cap 2 b has a first surface 2 b′opposite to a second surface 2 b″. In the reference system of FIG. 1,also the first and the second surfaces 2 b′, 2 b″ are parallel to oneanother and to the XY plane.

According to an embodiment, the base substrate 2 a includes, or ismechanically and/or electrically coupled to, a printed-circuit board(PCB) configured to support electronic components and to provide therequired routing for the signals received and generated by theelectronic components, in a per se known way. In particular, theprinted-circuit board is arranged to directly face the chamber 4 so thatsuch electronic components can be housed within the chamber 4.

The PCB may be a rigid circuit board, a flexible circuit board or arigid-flex circuit board, according to the needs and is coupled directlyto the base substrate 2 a or, alternatively, through an interfaceelement such as a heat exchanger.

The cap 2 b is coupled to the base substrate 2 a by means of lateralwalls 2 c extending between the cap 2 b and the base substrate 2 a, sothat an inner chamber 4 of the package 2 is formed. The lateral walls 2c may be either integral with the cap 2 b or the base substrate 2 a (andcoupled, for example glued, to the other among the cap 2 b and the basesubstrate 2 a); alternatively the lateral walls 2 c can be a separateelement, coupled (for example, glued) to both the cap 2 b and the basesubstrate 2 a.

The first surface 2 a′ of the base substrate 2 a directly faces thechamber 4 (in particular, the first surface 2 a′ is in the chamber 4);analogously, the first surface 2 b′ of the cap 2 b directly faces thechamber 4 (in particular, the first surface 2 b′ is in the chamber 4).

A first supporting element 8 extends within the chamber 4 and has asurface 8 a defining a supporting plane that forms an angle of incline awith the first surface 2 a′ of the base substrate 2 a. The value of theangle a is in the range of 25-65 degrees, in particular 45 degrees(where α=0 degrees means that the surface 8 a is parallel to the firstsurface 2 a′ and α=90 degrees means that the surface 8 a is orthogonalto the first surface 2 a′).

Coupled to the surface 8 a of the supporting element 8, there is a firstreflector 10, in particular a reflector manufactured in MEMS technology(also known as micro-mirror). The first reflector 10 is in particular aMEMS reflector of a resonant type, configured to be coupled to anactuation system that, when operated, causes oscillation of the MEMSreflector in a substantially periodic way around a resting position.This is also known in the art as a “MEMS scanner”. Micro-mirrors, orMEMS scanners, of this type are, for example, disclosed in U.S. Pat. No.9,843,779, and in U.S. Application for Patent No. 2018/0180873 (bothincorporated herein by reference). Other types of reflectors ormicro-mirrors can be used, as apparent to the skilled person in the art.

The first reflector 10 can be coupled to the supporting element 8 bymeans of glue or other means such as soldering regions, die-attach film,etc.

The first supporting element 8 is, according to an embodiment, made ofthermally-conductive material such as metal. In this case, the firstsupporting element 8 has also the function of being a heat-sink, forfavoring heat dispersion of the first reflector 10 when it is in theform of a MEMS micro-mirror or MEMS scanner and is biased, during use,through electric signals that cause temperature increase by Jouleeffect.

Coupled to the first surface 2 a′ of the base substrate 2 a there is anemitter 12, in particular a Vertical-Cavity Surface-Emitting LASER(VCSEL). The emitter 12 is coupled to the base substrate 2 a through thePCB, in a per se known way. In an embodiment, the emitter 12 is aninfrared (IR) emitter, configured to emit an IR radiation.

A second supporting element 14 extends within the chamber 4 and has asurface 14 a defining a supporting plane that forms an angle of inclineβ with the first surface 2 a′ of the base substrate 2 a. The value ofthe angle β is in the range 25-65 degrees, in particular 45 degrees(where β=0 degrees means that the surface 14 a is parallel to the firstsurface 2 a′ and (β=90 degrees means that the surface 14 a is orthogonalto the first surface 2 a′). It is noted that the same angle of inclineis formed at the intersection between the surface 14 a and the firstsurface 2 b′ of the cap 2 b (where β=0 degrees means that the surface 14a is parallel to the first surface 2 b′ and β=90 degrees means that thesurface 14 a is orthogonal to the first surface 2 b′).

In the embodiment of FIG. 1, the surfaces 8 a and 14 a of the first and,respectively, second supporting elements 8, 14 are parallel to oneanother.

Coupled to the surface 14 a of the supporting element 14, there is asecond reflector 16, in particular a mirror of a fixed type (such thatit does not oscillate like the first reflector 10).

The first supporting element 8 (with the first reflector 10) and thesecond supporting element 14 (with the second reflector 16) are arrangedin the chamber 4 in such a way that, when the electronic module 1 isconsidered in lateral cross section as in FIG. 1, the emitter 12 isarranged between the first supporting element 8 and the secondsupporting element 14. Furthermore, the surface 8 a and the surface 14 aface one another, so that also the first and second reflectors 10, 16face one another.

The cap 2 b is provided with a first window 20, arranged above, and at adistance from, the first reflector 10. In particular, the first window20 is superposed (or at least partially aligned along Z axis) to thefirst reflector 10. However, as is apparent from the previousdescription, the first window 20 lies on a plane parallel to the XYplane, while the first reflector 10 lies on a plane inclined 45 degreeswith respect to the XY plane.

The emitter 12 is furthermore arranged in such a way that a beam 18emitted, during use, by the emitter 12 is directed towards the secondreflector 16. The second reflector 16 is arranged in such a way that thebeam 18 is reflected towards the first reflector 10. The first reflector10 is arranged in such a way that the beam 18 thus received is reflectedtowards the first window 20. This condition is verified, for example,when the following conditions are verified: (i) the first and secondreflectors 10, 16 are arranged on the respective supporting elements 8,14 inclined by 45 degrees with respect to the XY plane (as discussedabove); and (ii) the beam 18 emitted by the emitter 12 is directed alongthe Z axis (which is orthogonal to the XY plane). Other respectivearrangements of the emitter 12 (beam 18), first reflector 10 and secondreflector 16 may be used, provided that the beam 18 is reflected by thefirst reflector 10 towards the first window 20.

The first window 20 includes an aperture through the cap 2 b to which isoptionally coupled a lens (for example used to magnify the beamreflected by the first reflector 10). Such lens is, for example, basedon Wafer-Level Optics (WLO) technology, which enables the design andmanufacture of miniaturized optics at the wafer level usingsemiconductor-like techniques.

Alternatively, when a lens is not provided, another protection elementmay be present at the first window 20, to prevent particulate, dust,etc. to enter within the chamber 4 and compromise the functioning of theelectronic module 1. In general, such lens/protection element is of amaterial that allows the beam 18 to pass through it and exit from thechamber 4, so that a beam is generated as output from the electronicmodule 1.

The chamber 4 further houses a detector 22, configured to detect areceived beam 24 from an environment external to the chamber 4. Thedetector 22 is, for example, mechanically coupled to the first surface 2a′ of the base substrate 2 a, in a per se known way.

According to an embodiment, the detector 22 is an IR detector configuredto detect a received IR radiation. In particular, a Single-PhotonAvalanche Diode (SPAD) can be used as detector 22.

The cap 2 a further comprises a second window 26, that includes anaperture through the cap 2 b, to which is optionally coupled arespective lens (for example to focus the received beam 24 and/or tocorrect aberration).

When a lens is not present at the second window 26, another respectiveprotection element may be present to prevent particulate, dust, etc. toenter within the chamber 4 and compromise the functioning of theelectronic module 1. In general, the lens/protection element coupled tothe second window 26 is of a material that allows the received beam 24to pass through it and enter the chamber 4, so that the received beam 24is an input to the electronic module 1.

The second window 26 is above, and at least partially aligned along Zaxis to, the detector 22 (the second window 26 is in particularsuperposed to the detector 22, at a distance from the detector 22, or incontact with it). In particular, the second window 26 and the detector22 are reciprocally arranged such that the received beam 24 passingthrough the second window 26 is directed towards a sensing portion ofthe detector 22, to be detected. The proposed architecture allows theintegration in a same package of VCSEL laser diode as light source(generally, an emitter) and a SPAD (generally, a detector), withsignificant impact on the reduction of costs and dimensions. Byintegrating all the components in a package-level module, the volumes ofthe module are reduced and optimized. By reducing the dimensions, theproposed solution enables better integration of 3D sensing applicationsinto portable devices and mobile phones.

FIG. 2 shows an electronic module 40 according to a further embodiment.Features of the electronic module 40 common to the electronic module 1are identified with the same reference numerals, and not furtherdescribed. In the electronic module 40 of FIG. 2, one or more amongelectronic circuitry 30 for controlling the emitter 12 (for controllingthe generation of the beam 18), electronic circuitry 32 for driving themicro-mirror 10 and electronic circuitry 34 for processing the signaltransduced by the detector 22 are integrated within the base substrate 2a. Further circuitry, configured to carry out further computationrequired by a specific application, may also be integrated within thebase substrate 2 a. Accordingly, the integration level is still furtherenhanced. The use of a MEMS scanner for implementing the first reflector10 allows to reduce and to compact the dimensions and to achieve at thesame time a high resolution.

It is noted that the supporting elements 8 and 14 may either bemechanically coupled, or fixed, to the base substrate 2 a, the cap 2 bor to both the base substrate 2 a and the cap 2 b.

FIG. 3 shows an electronic module 50 according to a further embodiment.Features of the electronic module 50 common to the electronic module 1and/or 40 are identified with the same reference numerals, and notfurther described.

The electronic module 50 includes a first supporting element 8 having awedge-like shape, that rests on, and is fixed to, the base substrate 2 aonly (at the first surface 2 a′). The first supporting element 8 may ormay not reach the first surface 2 b′ of the cap 2 b. The secondsupporting element 14 is an inclined wall fixed to the cap 2 b only (atthe first surface 2 b′) and may or may not reach the first surface 2 a′of the base substrate 2 a.

In particular, in FIG. 3, the second supporting element 14 does notreach (is not in contact with) the base substrate 2 a.

The first supporting element 8 may be formed integral with the basesubstrate 2 a, or as a separate body coupled to the base substrate 2 aby means of glue, soldering paste, or other mechanical means, forexample, screws. Analogously, the second supporting element 14 may beformed integral with the cap 2 b, or as a separate body coupled to thecap 2 b by means of glue, soldering paste, or other mechanical means,for example screws.

The electronic circuitry 30-34 described with reference to FIG. 2 can bepart of the embodiment of FIG. 3, or it may be absent (it is not shownin FIG. 3).

FIG. 4 shows a further embodiment, illustrating an electronic module 60.Features of the electronic module 60 common to the electronic module 1or 40 or 50 are identified with the same reference numerals, and notfurther described.

The electronic module 60 further comprises, with respect to theembodiment of FIG. 3, a lens module 62 arranged within the chamber 4 andprovided with a first lens 62 a operatively coupled to the emitter 12and a second lens 62 b operatively coupled to the detector 22. To thisend, a frame structure 62 c surrounds and sustain the lenses 62 a, 62 b.The frame structure 62 c can be coupled to the base substrate 2 a withinthe chamber 4 through a supporting element 64 arranged next to thelateral walls 2 c. The supporting element 64 may also be formed in adifferent way, for example as disclosed with reference to FIGS. 6A, 6Band FIGS. 9A, 9B.

The first lens 62 a is made of, for example, glass or plastic, and isconfigured to focus onto the second reflector 16 the beam 18 generatedby the emitter 12. The second lens 62 b is made of, for example, glassor plastic, and is configured to focus the incoming beam 24 onto thedetector 22. The lenses 62 a and 62 b are, for example, based onWafer-Level Optics (WLO) technology.

The first supporting element 8 corresponds to that already describedwith reference to FIG. 3, but it may also be replaced by that of FIG. 1or FIG. 2. The second supporting element 14 corresponds to thatdescribed with reference to FIG. 3, such that the lens module 62 extendsbetween the base substrate 2 a (above the emitter 12 and the detector22) and the supporting element 14.

The electronic circuitry 30-34 described with reference to FIG. 2 can bepart of the embodiment of FIG. 4, or it may be absent (not shown in FIG.4). Also, the wedge-shaped supporting element 8 of FIG. 3 can be part ofthe embodiment of FIG. 4, or supporting element 8 may be manufactured ina different way, for example as shown in FIG. 1. FIGS. 5A-11 illustratesa method for manufacturing (specifically, assembling) an electronicmodule 80 (shown in FIG. 11 at the end of manufacturing steps).

With reference to FIG. 5A, which is a lateral cross-sectional view (onplane XZ), the base substrate 2 a is provided. Here, the base substrate2 a is in particular an organic substrate with ICs laminated inside. Alaminated material such as FR-4 or BT (bismaleimide triazine) can beused. Alternatively, the base substrate 2 a is of plastic material or ofsemiconductor material.

The base substrate 2 a integrates the electronic circuitry 30 forcontrolling the emitter 12, the electronic circuitry 32 for driving themicro-mirror 10 and the electronic circuitry 34 for processing thesignal transduced by the detector 22. On the first surface 2 a′ of thebase substrate 2 a one or more pads 70 are provided for supplying thedriving signals for the first reflector 10 in case the latter isimplemented by means of a micro-mirror or MEMS scanner. The one or morepads 70 are electrically coupled to the electronic circuitry 32 throughmetallic routing path(s) provided within the substrate 2 a.

On the first surface 2 a′ of the base substrate 2 a the detector 22 iscoupled, for example by means of glue, die attach film, solder joints,etc. The detector 22 is electrically coupled to the electronic circuitry34 through metallic routing path(s) provided within the substrate 2 a,for receiving the signals transduced by the detector 22.

The reciprocal arrangement of the elements shown in FIG. 5A is forillustrative purpose only, and is not limitative of this disclosure.

FIG. 5B is a top-plan view (on XY plane) of FIG. 5A.

Then, as shown in FIG. 6A, a spacer structure 72, configured to form aninterface for mounting the lateral walls 2 c and the cap 2 b on the basesubstrate 2 a, is coupled to the base substrate 2 a, in particular atperipheral portions of the base substrate 2 a. As it can be appreciatedin the following, the spacer structure 72 is configured to sustain thelateral walls 2 c and the cap 2 b, and at the same time has the functionof the supporting element 64 described with reference to FIG. 4.

As it can be appreciated from the top-plan view of FIG. 6B, the spacerstructure 72 completely surrounds a superficial region of the basesubstrate 2 a where the detector 22 is located and where, duringsuccessive steps of manufacturing, the first supporting element 8 andthe emitter 12 will be arranged.

With reference to FIG. 7A the first supporting element 8 is coupled tothe base substrate 2 a through a layer of glue.

FIG. 7B is a top-plan view (on XY plane) of FIG. 7A.

The first supporting element 8 is, in particular, a solid body of metalmaterial having the further function of heat-sink for the firstreflector 10, as already discussed previously. Furthermore, in theembodiment of FIG. 7A, the supporting element 8 is provided with a firstportion 8′ including the inclined surface 8 a, and with a second portion8″ extending in continuity with the first portion 8′ and having arespective surface 8 b parallel to the XY plane. The second portion 8″is configured to, and has the function of, supporting the emitter 12 andoperates as a heat-sink for the emitter 12.

In FIGS. 7A, 7B, the first and second portions 8′, 8″ are integral withone another; however, according to a different embodiment, the first andsecond portions 8′, 8″ may be two separate elements.

With reference to FIG. 8A, a PCB 76, in particular a rigid-flex circuit,is coupled to the supporting element 8, for example by means ofthermally conductive glue.

The rigid-flex circuit 76 includes a first rigid portion 76 a coupled tothe first portion 8′ of the supporting element 8 and a second rigidportion 76 b coupled to the second portion 8″ of the supporting element8. A flexible portion 76 c connects the first rigid portion 76 a to thesecond rigid portion 76 b. The flexible portion 76 c extends at theintersection between the first portion 8′ and the second portion 8″, sothat it can follow the change in slope between the first portion 8′ andthe second portion 8″. The first rigid portion 76 a carries the firstreflector 10 and the second rigid portion 76 b carries the emitter 12.Alternatively to the embodiment shown in the drawings, the electronics34 that controls/drives the emitter 12 is not integrated within the basesubstrate 2 a, but it can be integrated into, or mechanically coupledto, the second rigid portion 76 b.

A further flexible portion 76 d is connected at one end to the secondrigid portion 76 b and at another end to the pad(s) 70, for supplyingthe driving signals and the power supply to the first reflector 10 andto the emitter 12. Other means alternative to, or in addition to, theflexible portion 76 c can be provided, for example wire bonding.

FIG. 8B is a top-plan view (on XY plane) of FIG. 8A.

With reference to FIG. 9A, the lens module 62 disclosed with referenceto FIG. 4 is provided and arranged in such a way that the first lens 62a is operatively coupled to the emitter 12 and the second lens 62 b isoperatively coupled to the detector 22. The frame structure 62 c iscoupled to, and sustained by, the spacer structure 72.

FIG. 9B is a top-plan view (on XY plane) of FIG. 9A.

FIG. 10 shows, in a lateral cross-sectional view taken on XZ plane, ofthe cap 2 b, which is formed integral with the lateral walls 2 c.Integral with the cap 2 b is also present the second supporting element14, with the second reflector 16 coupled to it. The extension, measuredalong the Z-axis, of the second supporting element 14, is less than theextension, measured along the Z-axis, of the lateral walls 2 c, so thatwhen the cap 2 b is mounted on the base substrate 2 a the secondsupporting element 14 is at a distance from the lens module 62.

The cap 2 b is here provided with the first and second window 20, 26, towhich, in turn, a further lens module 78 is coupled. In particular, thelens module 78 includes a first lens 78 a and a second lens 78 b. Thefirst lens 78 a is operatively coupled (and aligned) to the firstreflector 10 to receive the beam reflected by the first reflector 10,while the second lens 78 b is operatively coupled (and aligned along theZ axis) to the detector 22. The first lens 78 a is made of glass orplastic and is configured to magnify the output radiation 18 (forexample it is a divergent lens). The second lens 78 b is made of glassor plastic, and is configured to focus the incoming beam 24 on thedetector 22 and/or correct aberrations of the incoming beam 24. Thelenses 78 a and 78 b are, for example, based on Wafer-Level Optics (WLO)technology.

A frame structure 78 c surrounds and holds the lenses 78 a, 78 b. Theframe structure 78 c is, for example, coupled on top of the cap 2 b.

The lateral walls 2 c can be coupled to the spacer structure 72 througha coupling region made of at least one among glue, solder paste.

The cap 2 b and the lateral walls 2 c are made of at least one among:plastic material, metallic material, semiconductor material.

FIG. 11 shows, in a lateral cross-sectional view taken on XZ plane, thecap 2 b of FIG. 10 coupled to the structure of FIG. 9A, to form theelectronic module 80 according to the respective embodiment.

The electronic module 1, 40, 50, 60 disclosed, with reference to therespective embodiments of FIGS. 1-4 and FIG. 11, can be used as atime-of-flight device/camera to perform 3D sensing, for example forsmartphones applications, such as face recognition. In this context,direct or sinusoidal short light flashes (beam 18) are emitted by theemitter 12; the beam outputted from the first window 20 impinges onto anobject, is reflected back, and enters the chamber 4 through the secondwindow 26. The received beam 24 is then captured by the detector 22. Thetravel time of the light from the emitter 12 to the object and back tothe detector 22 is calculated by a computing circuit (for example, aprocessor, or processing unit). The computing circuit may be eitherintegrated within the base substrate 2 a or provided external to theelectronic module 80. The measured coordinates then generate a 3Dpicture of the object. The processing details and calculation of thetime of flight is understood by those of ordinary skill in the art andtherefore will not be described in detail herein.

The electronic module 80 can also be used in the context of structuredlight applications for 3D sensing. In this case, the detector 22 ispreferentially a CMOS sensor formed by a matrix of pixels, configured todetect an image from the incoming beam 24. Processing algorithms, knownin the art, can be used to acquire information from the detected imageto perform 3D sensing, such as face recognition.

FIG. 12 schematically shows a system 90, in particular a 3D scanningdevice or 3D scanner, including at least one electronic module 1, 40,50, 60, according to the respective embodiment, operatively coupled to aprocessing unit 92 that is configured to perform 3D sensing based on astructured light approach, a time-of-flight approach, or the like. As anexample, in case of time-of-flight approach, the processing unit 92 isconfigured to calculate a travel time between a first time instant,corresponding to generation of the first radiation 18 by the emitter 12,and a second time instant, corresponding to the detection of the secondradiation 24 by the detector 22, so as to determine the travel time ofthe beam from the emitter 12 to the object and back to the detector 22.Irrespective of the approach used, a 3D image of the object can bereconstructed by the processing unit 92, in a per se known way.

The processing unit 92 can be integrated in the base substrate 2 a or beexternal to the electronic modulel, 40, 50, 60. The system 90 implements3D sensing application(s), in particular for face recognition. Thesystem 90 is, generally, an electronic device, more in particular aportable electronic device, such as a smartphone, a tablet, a notebook;or, alternatively, a desktop computer.

From an examination of the characteristics of this disclosure providedaccording to the present disclosure, the advantages that it affords areevident.

The proposed architecture allows the integration of a light source(emitter, in particular a VCSEL laser diode), with significant impact onlowering of cost and dimensions. By integrating all the components in apackage level module, the volumes of the solution is reduced andoptimized. By reducing the dimensions, the proposed solution enables theintegration into portable devices and mobile phones.

Finally, it is clear that modifications and variations may be made towhat has been described and illustrated herein, without therebydeparting from the sphere of protection of this disclosure, as definedin the annexed claims.

1. A method of manufacturing an electronic module, comprising:integrating electronic circuitry for controlling an emitter andelectronic circuitry for processing a detector output signal into a basesubstrate having a first surface; providing a first supporting elementformed from a solid body of metal acting as a heat-sink and having afirst portion with an inclined top surface, and affixing the firstsupporting element to the first surface of the base substrate such thatthe inclined top surface of the first supporting element is inclinedwith respect to the base substrate; coupling a first reflector to theinclined top surface of the first portion of the first supportingelement such that a rear surface of the first reflector is in physicalcontact with the inclined top surface of the first portion of the firstsupporting element; configuring a spacer structure to form an interfacefor mounting lateral walls to the base substrate, and positioning a capover and supported by the lateral walls to thereby define a chamber;coupling the emitter to the first surface of the base substrate in afashion such that the emitter is connected to the electronic circuitryfor controlling the emitter; and affixing a detector to the firstsurface of the base substrate in a fashion such that the detector isconnected to the electronic circuitry for controlling the detector. 2.The method of claim 1, wherein affixing the first supporting elementcomprises gluing the first supporting element to the first surface ofthe base substrate.
 3. The method of claim 1, wherein the firstsupporting element is formed from the solid body of metal to have asecond portion extending parallel to the base substrate when the firstsupporting element is affixed to the first surface of the basesubstrate.
 4. The method of claim 3, wherein coupling the emittercomprises coupling the emitter to the second portion of the firstsupporting element.
 5. The method of claim 4, wherein the firstsupporting element is formed from the solid body of metal such that thefirst and second portions of the first supporting element are integrallyformed.
 6. The method of claim 4, wherein the first supporting elementis formed from the solid body of metal such that the first and secondportions of the first supporting element are separate from one anotherand spaced apart from one another.
 7. The method of claim 4, furthercomprising thermally coupling a rigid-flex circuit to the inclined topsurface of the first supporting element by: thermally coupling a firstrigid portion of the rigid-flex circuit to the first portion of thefirst supporting element; thermally coupling a second rigid portion ofthe rigid-flex circuit to the second portion of the first supportingelement; and connecting the first and second rigid portions of therigid-flex circuit using a flexible portion; wherein the flexibleportion extends at an intersection between the first rigid portion andthe second rigid portion such that it follows a change in slope betweenthe first and second portions of the first supporting element; whereincoupling the emitter comprises affixing the emitter to the second rigidportion of the rigid-flex circuit; and wherein coupling the firstreflector comprises affixing the first reflector to the first rigidportion of the rigid-flex circuit.
 8. The method of claim 7, wherein theelectronic circuitry for controlling the emitter is integrated into thesecond rigid portion of the rigid-flex circuit.
 9. The method of claim7, further comprising connecting a first end of a further flexibleportion of the rigid-flex circuit to the second rigid portion andconnecting a second end of the further flexible portion of therigid-flex circuit to one or more pads for supplying driving signals andpower supply to the first reflector.
 10. The method of claim 1, whereinthe spacer structure is also configured to completely surround a regionof the base substrate in which the first supporting element, firstreflector, emitter, and detector are located.
 11. The method of claim 1,further comprising providing the spacer structure to be made fromplastic material, metallic material, and/or semiconductor material; andfurther comprising providing the base substrate to be made from anorganic material, plastic material, and/or semiconductor material. 12.The method of claim 1, further comprising providing the cap to include asecond supporting element extending from an interior surface of the captoward the emitter; and further comprising affixing a second reflectorto the second supporting element.
 13. A method of manufacturing anelectronic module, comprising: integrating electronic circuitry forcontrolling an emitter and electronic circuitry for processing adetector output signal into a base substrate having a first surface;coupling a first reflector to a first surface of the base substrate;configuring a spacer structure to form an interface for mounting lateralwalls to the base substrate, and positioning a cap over and supported bythe lateral walls to thereby define a chamber; coupling the emitter tothe first surface of the base substrate in a fashion such that theemitter is connected to the electronic circuitry for controlling theemitter; affixing a detector to the first surface of the base substratein a fashion such that the detector is connected to the electroniccircuitry for controlling the detector; providing a lens moduleincluding first and second lenses; and positioning the lens modulewithin the chamber such that it is supported by the spacer structure andextends therefrom parallel to the substrate such that the first lens isoperatively coupled to the emitter and the second lens is operativelycoupled to the detector.
 14. The method of claim 13, wherein the spacerstructure is also configured to completely surround a region of the basesubstrate in which the first reflector, emitter, and detector arelocated.
 15. The method of claim 13, further comprising providing thespacer structure to be made from plastic material, metallic material,and/or semiconductor material; and further comprising providing the basesubstrate to be made from an organic material, plastic material, and/orsemiconductor material.
 16. The method of claim 13, further comprisingproviding the cap to include a second supporting element extending froman interior surface of the cap toward the emitter; and furthercomprising affixing a second reflector to the second supporting element.